1. Field of the Invention
The present invention relates to conductive hard tile flooring materials coated with a water soluble and photo-curable antistatic resin having excellent wear resistance and transparency and, more particularly, to a water soluble and photo-curable antistatic compound with improved wear resistance and high transparency for hard coating, as well as a conductive tile flooring material having a double-layer laminated structure coated with the antistatic compound, so that the flooring material can protect the surface of a conductive tile flooring against external wear, inhibit electrostatic discharge damage and transmit at least 80% of the original color of the conductive tile flooring.
2. Description of the Related Prior Art
Since higher-level integration of electronic parts and/or semiconductor devices has historically caused a significant problem in relation to failure of such products, many studies and efforts have been performed in order to considerably reduce electrostatic discharge failures of electronic parts and/or semiconductor devices.
Electrostatic discharge generated by workers in processes of manufacturing, assembling, packaging and/or delivering electronic parts, or in working environments with packaging materials and/or various instruments as well as fine particles such as dust deposited onto electronic parts and products (hereafter referred to as “electronics”), have become a more frequent cause of failure of the electronics.
Therefore, storage and delivery cases required for manufacturing or assembling electronics, as well as the entire surroundings of a working place including the floor must have antistatic performance. In order to protect electronics and/or semiconductor devices in the manufacturing environment, a clean-room system is well known to remove fine particles including dust. However, conventional conductive tile flooring materials for clean-room installations, which are usually prepared of rubber or PVC (polyvinyl chloride) resin, are susceptible to wear caused by dropping of instruments or other things, generating fine wear particles, so that the clean-room does not play its important role in manufacturing of electronics and/or semiconductor devices.
Conductive tile flooring materials are well known in prior arts including, for example: Korean Patent No. 10-427554, entitled “PVC carpet tile using carbon black and the method of manufacturing thereof”, which disclosed a conductive PVC carpet tile with a laminated structure of PVC resin layer containing carbon black, a glass fiber layer, a non-woven fabric layer, a fiber layer woven with carbon black containing yarns, etc.; and Korean Patent No. 10-589279, entitled “Conductive marble flooring and method of making the same by a continuous process”, which disclosed a decorative flooring with marble effect and stable conductivity obtained by a uniform composition of conductive carbon black and back-printing the rear side of the flooring with conductive carbon black ink. Briefly, the conductive flooring materials reported in these documents achieve their antistatic property by application of carbon black or through a fiber layer woven of yarns containing carbon fiber.
However, such flooring materials necessarily lead to the generation of fine wear particles due to the limited wear resistance of conductive tiles made of plastic such as rubber or PVC, and thus are not eco-friendly, not effective, and may lead to operational failure of electronic devices and parts.
Also, photo-curable coating compounds are well known in prior arts that include, for example: Korean Patent No. 10-246036, entitled “Anti-static and abrasion resistant UV curable acrylic coating composition”, which disclosed a UV curable coating compound containing conductive microfine particulate sol; Korean Patent No. 10-373207, entitled “Light curable anti-static and abrasion resistant coating composition”, which disclosed a coating compound comprising fine conductive particles as well as mono-functional and multi-functional acrylate monomers; and Korean patent application No. 2002-7013227, entitled “Composition for antistatic coat, antistatic hard coat, process for producing the same, and multilayered film with antistatic hard coat”, which disclosed an antistatic hard coating compound prepared by adding fine conductive particles with a diameter of 10 to 30 nm to multi-functional acrylate together with a silicon compound. The photo-curable resin compounds claimed in the above documents are for improvement of coating characteristics such as antistatic property and wear resistance, etc. But, due to excess charging of the fine conductive particles, these compounds cannot endow transparency to an oligomer comprising, for example, acrylate as a primary ingredient.